一、儲能變流器是雙向還是單向

儲能變流器（PCS）又(you)稱儲能(neng)逆變器，是連接儲能(neng)電(dian)池系統和電(dian)網的雙(shuang)向(xiang)電(dian)流(liu)可控轉(zhuan)換裝置，能(neng)夠在(zai)電(dian)網和儲能(neng)系統間精確快速地調(diao)節電(dian)壓、頻(pin)率、功率，實現恒功率恒流(liu)充放電(dian)以及平滑(hua)波動性(xing)電(dian)源(yuan)輸出。

儲能(neng)(neng)(neng)變流(liu)器(qi)不僅能(neng)(neng)(neng)滿(man)足傳(chuan)統并網變流(liu)器(qi)對直流(liu)電(dian)(dian)(dian)轉(zhuan)換為交(jiao)流(liu)電(dian)(dian)(dian)的逆變要求，還可滿(man)足儲能(neng)(neng)(neng)系統“充(chong)電(dian)(dian)(dian)+放(fang)電(dian)(dian)(dian)”帶來(lai)的雙向(xiang)變流(liu)需求，具有對電(dian)(dian)(dian)池充(chong)電(dian)(dian)(dian)和放(fang)電(dian)(dian)(dian)功能(neng)(neng)(neng)，可用(yong)于(yu)光伏、風力(li)發(fa)電(dian)(dian)(dian)功率(lv)平(ping)滑、削峰填谷、微型(xing)電(dian)(dian)(dian)網等多種場合。

并網模式(shi)下，在(zai)(zai)負荷低谷(gu)期，儲(chu)能變流(liu)器把電(dian)(dian)網的(de)交流(liu)電(dian)(dian)整流(liu)成(cheng)直(zhi)流(liu)電(dian)(dian)給電(dian)(dian)池組充(chong)電(dian)(dian)，在(zai)(zai)負荷高峰(feng)期，儲(chu)能變流(liu)器把電(dian)(dian)池組中的(de)直(zhi)流(liu)電(dian)(dian)逆變成(cheng)交流(liu)電(dian)(dian)反送到電(dian)(dian)網中。

離網模式下，儲能(neng)變流器(qi)與主電(dian)(dian)網脫開(kai)，給(gei)本地的部分負荷提供滿足電(dian)(dian)網電(dian)(dian)能(neng)質量要求(qiu)的電(dian)(dian)能(neng)。

二、雙向儲能變流器的工作模式有哪些

雙向儲(chu)能(neng)變流器(qi)pcs的工作模式分為并網模式、離(li)網模式和混合模式。

1、并網模式

并(bing)網(wang)(wang)模式(shi)下(xia)包括充(chong)電(dian)(dian)(dian)功能(neng)和放(fang)電(dian)(dian)(dian)功能(neng)，此時用戶(hu)可(ke)以選(xuan)擇(ze)自動(dong)模式(shi)和手動(dong)模式(shi)。在自動(dong)模式(shi)下(xia)，如果用戶(hu)選(xuan)擇(ze)并(bing)網(wang)(wang)充(chong)電(dian)(dian)(dian)或(huo)放(fang)電(dian)(dian)(dian)狀態，儲能(neng)逆(ni)變器(qi)將以之前設定好(hao)的值(zhi)對蓄電(dian)(dian)(dian)池進行充(chong)電(dian)(dian)(dian)或(huo)放(fang)電(dian)(dian)(dian)。在手動(dong)模式(shi)下(xia)，用戶(hu)可(ke)以通過手動(dong)修(xiu)改充(chong)電(dian)(dian)(dian)或(huo)放(fang)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)、電(dian)(dian)(dian)壓和時間值(zhi)，使儲能(neng)逆(ni)變器(qi)工作在設定的充(chong)電(dian)(dian)(dian)或(huo)放(fang)電(dian)(dian)(dian)狀態。

并網模式中，儲能逆變器連接在一個大容量公用電網中，大容量是指該電網的總容量至少比儲能逆變器容量大10倍以上。并網模式的主要特征是儲能逆變器必(bi)須(xu)(xu)與(yu)存在的(de)電(dian)網(wang)頻率同(tong)步(bu)。要做(zuo)到與(yu)電(dian)網(wang)同(tong)步(bu)，儲能(neng)逆(ni)變器相對(dui)于(yu)電(dian)網(wang)來說作為(wei)一個(ge)電(dian)流源。有些(xie)情(qing)況下(xia)，儲能(neng)逆(ni)變器必(bi)須(xu)(xu)能(neng)通過無(wu)功控(kong)制為(wei)電(dian)網(wang)提供(gong)電(dian)壓支持。該(gai)模式常用(yong)于(yu)削峰填谷、電(dian)力負載(zai)平衡和調節電(dian)能(neng)質量。

2、離網模式

孤(gu)島系(xi)統(tong)(tong)是(shi)一(yi)(yi)個(ge)(ge)或多個(ge)(ge)發電(dian)(dian)(dian)(dian)系(xi)統(tong)(tong)并聯(lian)形成(cheng)一(yi)(yi)個(ge)(ge)局(ju)部(bu)的(de)“微(wei)網(wang)”。孤(gu)島系(xi)統(tong)(tong)的(de)主要特征是(shi)局(ju)部(bu)電(dian)(dian)(dian)(dian)網(wang)與(yu)(yu)(yu)所有(you)的(de)大電(dian)(dian)(dian)(dian)網(wang)脫離，儲(chu)能系(xi)統(tong)(tong)的(de)額定功(gong)率與(yu)(yu)(yu)局(ju)部(bu)電(dian)(dian)(dian)(dian)網(wang)產生的(de)總(zong)功(gong)率大致(zhi)相等。在(zai)這(zhe)個(ge)(ge)系(xi)統(tong)(tong)中，儲(chu)能系(xi)統(tong)(tong)必(bi)須可以(yi)充當網(wang)路電(dian)(dian)(dian)(dian)源，給局(ju)部(bu)電(dian)(dian)(dian)(dian)網(wang)提供電(dian)(dian)(dian)(dian)壓和頻(pin)率控(kong)制。另(ling)一(yi)(yi)方(fang)面(mian)，如果一(yi)(yi)個(ge)(ge)發電(dian)(dian)(dian)(dian)裝置(zhi)不能與(yu)(yu)(yu)其他發電(dian)(dian)(dian)(dian)裝置(zhi)同步，比如一(yi)(yi)個(ge)(ge)柴油發電(dian)(dian)(dian)(dian)機(ji)連(lian)接(jie)在(zai)局(ju)部(bu)電(dian)(dian)(dian)(dian)網(wang)上，那么儲(chu)能系(xi)統(tong)(tong)必(bi)須作為一(yi)(yi)個(ge)(ge)電(dian)(dian)(dian)(dian)源之同步。有(you)些情況下(xia)，儲(chu)能系(xi)統(tong)(tong)還要在(zai)作為電(dian)(dian)(dian)(dian)源和與(yu)(yu)(yu)發電(dian)(dian)(dian)(dian)裝置(zhi)同步之間(jian)轉(zhuan)換。

孤島系統的(de)特征(zheng)是儲(chu)能(neng)系統與(yu)局部電網相連(lian)，這些情(qing)形可能(neng)存在(zai)于偏遠山區(qu)或小島嶼。常見應(ying)用包(bao)括平滑由(you)可變(bian)電源可變(bian)負載(zai)引起的(de)功(gong)率波動，穩定電網，優化燃(ran)料的(de)使用和調節電能(neng)質量。

3、混合模式

儲能(neng)(neng)系(xi)統(tong)能(neng)(neng)夠(gou)在并網(wang)(wang)(wang)模(mo)式和離(li)網(wang)(wang)(wang)模(mo)式之(zhi)間進行(xing)切換。儲能(neng)(neng)系(xi)統(tong)處于微(wei)(wei)網(wang)(wang)(wang)中(zhong)，微(wei)(wei)網(wang)(wang)(wang)與公共電(dian)(dian)網(wang)(wang)(wang)接(jie)，正常工(gong)作(zuo)狀態下作(zuo)為(wei)并網(wang)(wang)(wang)系(xi)統(tong)運行(xing)如果微(wei)(wei)網(wang)(wang)(wang)與公共電(dian)(dian)網(wang)(wang)(wang)脫離(li)，儲能(neng)(neng)系(xi)統(tong)將工(gong)作(zuo)在離(li)網(wang)(wang)(wang)模(mo)式為(wei)微(wei)(wei)網(wang)(wang)(wang)提供(gong)主電(dian)(dian)源(yuan)。常見應用包括濾波，穩定(ding)電(dian)(dian)網(wang)(wang)(wang)，調(diao)節電(dian)(dian)能(neng)(neng)質量和創造自愈(yu)網(wang)(wang)(wang)。